1. Field of the Invention
The present invention relates to a frame structure which is containable by folding it into a compact shape, and more particularly to such frame structure which can be easily transported through aerospace and unfolded at a place desired so that it forms a plane or a three-dimensional structure having high degree of freedom.
2. Description of Prior Art
In a construction of large aerospace structure, construction works on the orbit has been increased and complicated as the structure has become larger, and thus facilities such as a construction robot on the orbit and works done by astronauts outside the spaceship are inevitable.
There is a technique for constructing large aerospace structure called “inflatable.” In this technique, first of all, a membrane structure is inflated by gas, and then the structure is solidified chemically and/or physically to form a structure. It seems that this structure is easily constructed and is extremely light-weight. However, it is difficult to control the shape of the structure being formed precisely. Therefore, applications of the technique are limited. In addition, the technique has a shortcoming that the structure is not highly recyclable.
In the case of solar batteries mounted on a satellite, many of such batteries employ an oblong plate which is folded when it is contained and expanded to a long plate on the orbit. These prior art structures have advantages that they are easily contained and their extension mechanisms are simple. However, on the other hand, they have problems that their ways of extension are limited in one-dimension, and they lack applicability and adoptability to larger structures.
Furthermore, when large space structures such as space stations are constructed in aerospace, it is desired to use all-purpose structural members which can be assembled by simple work, and it is required to transport such members efficiently. For example, a panel for a solar battery and antenna are usually folded into compact shapes and contained when they are transported, and unfolded on the orbit. However, the techniques provided so far do not always satisfy these requirements.